Heretofore, when transversely mounting an engine within an engine compartment at a front of a vehicle in such a manner as to allow a cylinder row direction to be oriented in a vehicle width direction, it has been a common practice to install the engine such that an intake manifold is located on a vehicle forward side of the engine. In order to achieve weight reduction, the intake manifold is made of a synthetic resin. In the case where a so-called direct injection engine configured to directly inject fuel into a combustion chamber is employed as such a transverse-mounted engine, a fuel distribution pipe (so-called “fuel rail”) capable of distributing fuel to respective cylinders is disposed between an engine and an intake manifold to extend in a cylinder row direction, wherein the fuel distribution pipe and the intake manifold are located in adjacent relation to each other.
Thus, in the event of a vehicle frontal collision, a radiator and others arranged in front of the intake manifold come into collision with the intake manifold, so that an impact of the inter-component collision is likely to cause the intake manifold to be displaced rearwardly, resulting in interference between the intake manifold and the fuel distribution pipe.
A structure of an intake manifold for resolving the risk of the interference is disclosed in JP 2012-158994A. The intake manifold described in JP 2012-158994A is constructed by joining a near-side divided segment on a near side with respect to an engine and a far-side divided segment on a far side with respect to the engine together, wherein the far-side divided segment is set to have strength less than that of the near-side divided segment.
In this intake manifold, during a vehicle frontal collision, the far-side divided segment is deformed at an earlier stage. Thus, an impact of the vehicle frontal collision is absorbed by the far-side divided segment to suppress deformation of the near-side divided segment, so that it becomes possible to suppress the occurrence of a situation where the intake manifold comes into interference with a fuel distribution pipe located between the intake manifold and the engine.
However, the intake manifold described in JP 2012-158994A is configured such that a front portion of the far-side divided segment approximately evenly receives the impact of the vehicle frontal collision. Therefore, the far-side divided segment is insufficient in terms of deformability, i.e., it cannot be said that the intake manifold has sufficient impact absorption capability.